Superheater



M. HARD SUPERHEATER March 2, 1937.

Filed June 23, 1936 INVENTOR ATTORNEY Patented Mar. 2, 1937 UNITEDSTATES PATENT OFFICE SUPER/HEATER Application June 23, 1936, Serial No.86,742

Claims.

The invention relates to superheaters for locomotive and similar boilersin which tubular superheating elements are located in boiler fiues, thetwo ends of each being secured to a header in 5 the smoke box.

In some forms of such tubular superheater elements it becomes importantthat the steam enter at one certain end of each element and leave at theother end and that the flow of he steam be not reversed. An illustrationof such an element is found in United States Patent No. 1,996,134,granted on April 2, 1935, to A. Williams.

The object of the present invention is to provide means for positivelyinsuring that the ele ments are not interchanged but are secured intheir proper places so that the steam flow in each element occurs in theright direction.

The invention will be described in connection with the accompanyingdrawing in which Fig. 1 is a top view of a superheater header (withporvide means for posiively insuring that the elements in place andlocated in two flues which are shown in section; Fig. 2 is a sectionalview on line 2--2 of Fig. 1; Fig. 3 is an enlarged view of some of theclamps and cooperating elements used to carry out the invention; andFig. 4 is a section through one of the clamps and associated washers inposition on the two ends of one of the elements.

The nature of the elements can readily be gathered from Figs. 1 and 2.Each element comprises a section I made up of an outer tube 3 and aninner tube 4 placed coaxially with each other and leaving an annularspace 5 between them. With this annular space communicate two tubes 1and 8, the former of which is directly connected to the header 9 and thelatter of which is connected to a serpentine portion II of the elementmade up of four tube lengths connected in series by return bends, thelast tube I3 of the series being extended through the interior of tube 4and leading to the header 9.

This unit is the subject of the above-named United States Patent1,996,134., where it is fully explained that the steam flow should be insuch direction that steam from the header flows successively through thepipe I, the annular space of the section I, and the separate section IIfrom which it is delivered back to the header. If the steam flow shouldbe reversed, the full benefits of this type of unit will not berealized.

In Fig. 2 there is shown in section a standard form of superheaterheader and it is assumed that the reader is familiar with this header.The header is fully described and illustrated in numerous prior UnitedStates patents, for example,1,124,493. The point of interest inconnection with the present invention is that the header comprises aseries of chambers to alternate ones of which saturated steam isdelivered from the boiler, the superheater units or elements, afterhaving superheated the steam, delivering it back to the interveningchambers. In the particular example used for illustration the chambersmarked with reference numeral I5 receive the saturated steam from theboiler and the superheater elements deliver the steam back insuperheated condition to the chambers marked with reference numerals II.

The means for securing these superheater elements to the header are alsowell known and 15 broadly do not form a part of the invention. Theycomprise bolts I9 extending through openings 2| in the header wallsseparating chambers II from chambers I 5. These bolts extend throughclamps 23 and carry nuts 25 on their lower ends. The element ends I andI3 carry washers 29 engaging the enlarged heads 2'! and resting onclamps 23. The washers 29 are forced by the clamps 23 against the heads21 and thus force the latter into engagement with the header when thenuts 25 are drawn up. An inspection of Figs. 1 and 2 will show that thesuperheater elements are of two kinds-left and right. In Fig. 1, forexample, there is shown a unit of one kind at the top and a unit of theopposite kind at the bottom. The two inlet ends I of the two units areadjacent to each other and in Fig. 2 it will be noted that they areconnected to the first saturated chamber I5 from the left end. Each ofthe saturated chambers I 5 similarly has two ends of neighboringelements connected to it; and similarly each superheated steam chamber II has two outlet ends I3 of adjacent elements connected to it. The twochambers I! at the two ends of the header form an exception, each havingonly one end I3 connected to it.

In the above, two elements have been specifically referred to which lieside by side and in the top'row of the fiues 3|. It will be understoodof course that there are several horizontal rows of dues 3 I. In Fig. 2,to illustrate this, there are shown at the right a number of flues 3Iconstituting one vertical row of flues. Each flue has located in it asuperheater element, the ends of the 2nd, 3rd, 4th, etc. row beingbrought forward of the ends I and I3 of the element illustrated andconnected to the header at points successively further forward. Thisnecessitates the use of a series of clamps 23 in a horizontal rowextending forward from the flue as is the usual practice. In theparticular example illustrated there are five rows of clamps since thereare five horizontal rows of fiues. All of this is in accordance with theusual well-known practice. The location and dimensions of each elementare such that a right hand unit could be placed where there should be aleft hand unit and vice versa, and it is the object of the presentinvention to provide means whereby such misplace ment of the units canbe positively prevented.

As a part of the means to prevent an interchange of left and right handunits the clamps 23 are placed on the elements in a permanent manner.This is done by having at least one end of each clamp equipped with anopening 33 through which the element end extends. In the form of clampillustrated the other end is left open-ended as at 35, the two branches3! and 39 forming a fork. This end could also be formed so as to presenta circular opening 33, but it is unnecessary to do this at both ends andthere are certain reasons of convenience why it is preferable to leaveone end open as shown.

Reference to Fig. 4 will make clear that the enlarged head 21 cannot beslipped through the opening 33. In addition, it will be noted that thewasher 29 on each branch is fixed permanently around its end 1 or E3.The washers and the clamps 23 are placed on the pipe ends duringfabrication and once put in place are there permanently.

It will be noted, from an inspection of Fig. 3 particularly, that thebranch 3'! is longer than the branch 39. This figure further shows onthe opposite end of a clamp a projection 4| in line with the longerbranch 31. The corner opposite it and 39 is clipped oiT or recessed asat 43.

The clamps on the left and right hand units are alike but are reversedin position. Thus in Figs. 1 and 3 the clamps in the top row have thelong branches 31 and the projection 4! toward the left whereas theclamps in the second row have the projections 4i and the longer branch31 of the fork at the right. The projections 4| of the clamps in thesecond row fit into the clipped or recessed corners of the clamps in thetop row.

The clamps of the third row are in a position similar to that of thefirst row and their longer ends 31 fit into the spaces left by theshorter fiues of the clamps in the second row. Throughout, alternaterows are in relatively reversed position and no element can be used inany given place unless it has the right sort of clamp. It is obviouslyessential that in the fabrication care must be exercised to put theclamps in one position on the elements of one kind and in the oppositeposition on those of the other kind.

In order tomake sure that the clamps in the outer rows are of thecorrect kind there is used at each end a plate 45. This is convenientlysecured in any preferred manner to the bracket 4! which carries theheader. This plate 45 is equipped with projections 41 and recesses 49 solocated as to lie respectively opposite the short and long branches ofthe fork of the outer row of clamps.

It will be clear that while one particular type of element has beenreferred to, the invention applies to other types where there are leftsand rights and that the above specific form of the invention describedmay in practice be modified without sacrificing its spirit and suchvariations are meant to fall within the scope of the appended claims.

What I claim is:

1. In a locomotive superheater of the type wherein tubular superheaterelements located in horizontal rows of fiues have their ends secured toa header having a row of chambers from alternate ones of which steam isdelivered to the elements, and to the intervening ones of which theelements deliver the steam after it is superheated, the elements beingof two kinds, one being left and the other right, the steam inlet andoutlet ends being reversed in one kind as compared with their order inthe other kind, theelemen'ts of each horizontal row being so connectedto the header that each chamber has two ends secured to it with theexception of each end chamber which each have only one end secured toit, means to prevent an element of the kind opposite that required beingused in any given position, said means comprising clamps irremovablyplaced on said elements and all in the assembled structure lying in oneplane, each clamp engaging the two ends of its element, a plate adjacentto each end of the row of clamps, the plates and clamps being so shapedthat only an element of the right one of the two kinds fits into anygiven place.

2. Apparatus of the kind defined in claim 1,

the clamps all being alike and each'having a projection at each endlaterally of a median longitudinal line through the clamp.

3. Apparatus of the kind defined in claim 1, the clamps all being alikeand each having a projection at each end laterally of a medianlongitudinal line through the clamp, the clamps of one of said kinds ofelement being in a reversed position compared with those of the otherkind.

4. Apparatus of the kind defined in claim 1, the clamps all being alikeand each having a pro jection at each end laterally of a medianlongitudinal line through the clamp, the clamps on one of said kinds ofelement being in reversed position compared with those of the otherkind, and the said plates being provided with recesses so located thatonly elements with the clamps in the right position can be placedadjacent to said plates.

5. Apparatus in accordance with claim 1, the clamps all being alike butthose of one kind of element being reversed relatively to those of theother kind, each clamp having a greater over-all length at one side ofthe median line than at the other side of the median line.

MALCOLM HARD.

